This article will elaborate on the third element, namely the inherent requirements of the rig:
holes location and drilling .
For the rig, if positioning is not correct, a direct result is drilling deviations ,which will affect the subsequent blasting effects and costs.
In daily drilling operations, there are two kinds of holes, vertical and with angel.
Vertical hole drilling is relatively easy, the easiest way is to promote the two pointers installed on the two vertical surfaces of the girder ,you can basically observe the vertical angle.
However, in reality, most of the drilling are angled in three dimensions, much more complex than the vertical hole.
If you pursuit precise drilling direction, then we need satellites’ help.
Currently there are two better systems, Sandvik TIM 3D system,and Atlas Copco HNS system,
The basic approach is :
1. Satellite scan the surface, then get the surface data
2. Regarding to the surface data and drilling requirements, develop detailed programs
3.The program is transmitted to the rig cab’s receiving apparatus
4.Does not require artificial drilling hole, satellite device will record the coordinates of each hole
5.Drillers see the screen, through the control handle to adjust to orginal drilling program, then complete the accurate positioning, begin holes drilling .(Sensor and positions receiver device on the rig will inform the drillers that if the position is accurate via screen. )
6.Besides the angle, depth settings can also be realized simultaneously. (Reducing the error of depth lack or excessive ).There’s even automatic switching rods function.Most of time, drillers just need to sit in front of the screen to work.
Under the ensurance of accurate position, the next step is drilling.
First, we must ensure the girder against the work surface completely, Otherwise, there will be deviation of the opening direction,at the same time, its runaway reaction also cause damage to the drilling rig and tools.
Second, on the surface, it is not advisable that take the whole forward, which be likely to cause deviation, but we should move slowly in the beginning, when full access to the rock joints increase the power.
Now, some advanced imported equipment in the opening part has intelligent control,but can not be completely accurate, also need drillers’ experience,to achieve accurate openings.